[PATCH] net: remove LLTX in atl2 driver

From: Kevin Hao
Date: Wed Sep 24 2008 - 20:35:55 EST


When NETIF_F_LLTX is set, the atlx driver will use a private lock.
But in recent kernels this implementation seems redundant and
can cause problems where AF_PACKET sees things twice. Since
NETIF_F_LLTX is marked as deprecated and shouldn't be used in
new driver, this patch removes NETIF_F_LLTX and adds a mmiowb
before sending packet.

Signed-off-by: Kevin Hao <kexin.hao@xxxxxxxxxxxxx>
---
drivers/net/atlx/atl2.c | 24 +-----------------------
drivers/net/atlx/atl2.h | 1 -
2 files changed, 1 insertions(+), 24 deletions(-)

diff --git a/drivers/net/atlx/atl2.c b/drivers/net/atlx/atl2.c
index b2995ac..3df4ee1 100644
--- a/drivers/net/atlx/atl2.c
+++ b/drivers/net/atlx/atl2.c
@@ -116,7 +116,6 @@ static int __devinit atl2_sw_init(struct atl2_adapter *adapter)
hw->max_frame_size = adapter->netdev->mtu;

spin_lock_init(&adapter->stats_lock);
- spin_lock_init(&adapter->tx_lock);

set_bit(__ATL2_DOWN, &adapter->flags);

@@ -749,11 +748,7 @@ static void atl2_down(struct atl2_adapter *adapter)
* reschedule our watchdog timer */
set_bit(__ATL2_DOWN, &adapter->flags);

-#ifdef NETIF_F_LLTX
- netif_stop_queue(netdev);
-#else
netif_tx_disable(netdev);
-#endif

/* reset MAC to disable all RX/TX */
atl2_reset_hw(&adapter->hw);
@@ -829,7 +824,6 @@ static inline int TxdFreeBytes(struct atl2_adapter *adapter)
static int atl2_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
{
struct atl2_adapter *adapter = netdev_priv(netdev);
- unsigned long flags;
struct tx_pkt_header *txph;
u32 offset, copy_len;
int txs_unused;
@@ -845,16 +839,6 @@ static int atl2_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
return NETDEV_TX_OK;
}

-#ifdef NETIF_F_LLTX
- local_irq_save(flags);
- if (!spin_trylock(&adapter->tx_lock)) {
- /* Collision - tell upper layer to requeue */
- local_irq_restore(flags);
- return NETDEV_TX_LOCKED;
- }
-#else
- spin_lock_irqsave(&adapter->tx_lock, flags);
-#endif
txs_unused = TxsFreeUnit(adapter);
txbuf_unused = TxdFreeBytes(adapter);

@@ -862,7 +846,6 @@ static int atl2_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
txs_unused < 1) {
/* not enough resources */
netif_stop_queue(netdev);
- spin_unlock_irqrestore(&adapter->tx_lock, flags);
return NETDEV_TX_BUSY;
}

@@ -908,8 +891,7 @@ static int atl2_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
ATL2_WRITE_REGW(&adapter->hw, REG_MB_TXD_WR_IDX,
(adapter->txd_write_ptr >> 2));

- spin_unlock_irqrestore(&adapter->tx_lock, flags);
-
+ mmiowb();
netdev->trans_start = jiffies;
dev_kfree_skb_any(skb);
return NETDEV_TX_OK;
@@ -1447,10 +1429,6 @@ static int __devinit atl2_probe(struct pci_dev *pdev,
netdev->features |= (NETIF_F_HW_VLAN_TX | NETIF_F_HW_VLAN_RX);
#endif

-#ifdef NETIF_F_LLTX
- netdev->features |= NETIF_F_LLTX;
-#endif
-
/* Init PHY as early as possible due to power saving issue */
atl2_phy_init(&adapter->hw);

diff --git a/drivers/net/atlx/atl2.h b/drivers/net/atlx/atl2.h
index 6e1f28f..09974df 100644
--- a/drivers/net/atlx/atl2.h
+++ b/drivers/net/atlx/atl2.h
@@ -462,7 +462,6 @@ struct atl2_adapter {
u16 link_duplex;

spinlock_t stats_lock;
- spinlock_t tx_lock;

struct work_struct reset_task;
struct work_struct link_chg_task;
--
1.5.6.2.220.g44701

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